Hematopoietic progenitor cells (such as bone marrow derived, CD34+ stem cells) promote the repair of diseased and damaged tissues and offer promise for the treatment of hereditary and acquired human diseases (Asahara et al. (1997) Science 275, 964-967; Rafii et al. (2003) Nat. Med. 9, 702-12; Takahashi et al. (1999) Nat. Med. 5, 434-438; Kawamoto et al. (2001) Circulation 103, 634-637; Hattori et al. (2001) J. Exp. Med. 193, 1005-1014; Otani et al. (2002) Nat. Med. 8, 1004-1010 (2002); Priller (2001) et al. J. Cell Biol. 155, 733-738; LaBarge et al. (2002) Cell. 111, 589-601; and Torrente et al. (2003) J. Cell Biol. 162, 511-520). For example, bone marrow derived, CD34+ stem cells promote neovascularization by differentiating into endothelial cells (Asahara et al. (1997) supra; Rafii et al. (2003) Nat. Med. 9, 702-12; Takahashi et al. (1999) Nat. Med. 5, 434-438; Kawamoto et al. (2001) Circulation 103, 634-637; Hattori et al. (2001) J. Exp. Med. 193, 1005-1014; Otani et al. (2002) Nat. Med. 8, 1004-1010 (2002); Priller (2001) et al. J. Cell Biol. 155, 733-738; LaBarge et al. (2002) Cell. 111, 589-601; Torrente et al. (2003) J. Cell Biol. 162, 511-520); Lyden et al. (2001) Nat. Med. 7, 1194-201; Ruzinova et al. (2003) Cancer Cell. 4: 277-289; Jain et al. (2003) Cancer Cell 3, 515-516; Religa et al. (2002) Transplantation 74, 1310-1315; and Boehm et al. (2004) J. Clin. Invest. 114, 419-426). Although neovascularization stimulates healing of injured tissue (Asahara et al. (1997) supra; Rafii et al. (2003) Nat. Med. 9, 702-12; Takahashi et al. (1999) Nat. Med. 5, 434-438; Kawamoto et al. (2001) Circulation 103, 634-637; Hattori et al. (2001) J. Exp. Med. 193, 1005-1014; Otani et al. (2002) Nat. Med. 8, 1004-1010 (2002); and Carmeliet (2003) Nat. Med. 9, 653-660), it nonetheless also promotes undesirable consequences such as tumor growth and inflammatory disease (Lyden et al. (2001) Nat. Med. 7, 1194-201; Ruzinova et al. (2003) Cancer Cell. 4: 277-289; Jain et al. (2003) Cancer Cell 3, 515-516; Carmeliet (2003) Nat. Med. 9, 653-660; and Hanahan et al. (1996) Cell 86, 353-364).
While the art appreciates some of the advantages of using hematopoietic progenitor cells, it remains unclear how hematopoietic progenitor cell adhesion, differentiation, and migration may be modulated. Thus, there remains a need for methods for altering hematopoietic progenitor cell adhesion and/or migration to a target tissue, and for altering hematopoietic progenitor cell differentiation into a second cell.